Electrical contact and connection means



Nov. 18, 1941. H. A. DOUGLAS 2,253,416

ELECTRICAL CONTACT AND CONNECTION MEANS Original Filed July 8, 1955 x0 jA 6/ /7 f 26 J 24 /a u'l'u il 1 Harry 17. 027/46 INVENTOR.

g M ATTORNEY.

Patented Nov. 18, 1941 ELECTRICAL CONTACT AND CONNECTION MEANS Harry A.Douglas, Bronson, Mich.

Original application July 8, 1935, Serial No. 30,282, now Patent No.2,166,345, dated July 18,

1939. Divided and this 1938, Serial N0. 197,156

3 Claims.

My invention relates to electrical contact and connection means, such asmay be used or embodied in electrical switches and the like, and moreparticularly to terminal receiving means for cooperation with so-calledsnap terminals and contact members associated with the terminalreceiving means, and the principal object of my invention is to providenew and improved electrical contact means of these types.

The present application is a division of my copending application,Serial Number 30,282, filed July 8, 1935, now Patent Number 2,166,345,issued July 18, 1939.

In the drawing accompanying this specification, and forming a part ofthis application, I have shown, for purposes of illustration, one formwhich my invention may assume. In the drawing:

Figure 1 is a view partly in longitudinal section and partly inelevation showing one embodiment of my invention, used in an electricswitch,

Figure 2 is a longitudinal section of one of the combined contact meansand terminal receiving means shown in Figure 1, the base of the switchbeing fragmentarily shown,

Figure 3 is a section taken on the line 3-3 of Figure 2, looking in thedirection of the arrows, with a plug conductor terminal added,

Figure 4 is a fragmentary perspective view of a detail of the base shownin Figure 1, and

Figure 5 is a perspective view of the disassembled parts of the combinedcontact means and terminal receiving means.

Referring in detail to the drawing, Figure 1 shows a switch I0 mountedon a panel II. The switch I0 includes relatively movable elementscomprising, in this instance, a rotatable insulating disc I2 carrying acontact plate I3 cooperable with a plurality of contacts I4, I5, I 6forming part of a plurality of unitary contactterminal posts I1, I8, I9supported by a base 20 in a manner to be further described. The base 20is fastened to and supportedinany suitable manner by a cup-shaped'casing2I, the end wall 22 of which is fastened to a tubular threaded member23, which is disposed through an aperture 24 in the panel II andfastened to the panel II in any suitable manner, as by nuts 25. Theinsulating disc I2 is carried in any suitable manner and rotatable by anoperating member 26 here shown in the form of a dished metallic discfastened to an end of an actuatin shaft 21, rotatably disposed withinthe tubular member 23. The other end of the shaft 21 is provided withapplication March 21,

an operating handle 28 suitably fastened thereto.

The contact-terminal post I8 is mounted in axial alignment with thecenter of the insulating disc I2 and the contact I5 of thecontactterminal post I8 is adapted to engage walls of a recess 29 formedin the contact plate I3. The contact I6 of the contact-terminal post I9is shown in engagement with another recess, 30, in the plate I3 spacedradially from the central recess 29; and the contact I4 of thecontact-terminal post I1 is shown in engagement with walls of a recess3| formed in the insulating disc I2 itself, spaced radially the samedistance from the central recess 29, so that, in the position of theparts shown, the contacts I5, I6 are electrically connected by the plateI3, whereas the contact I4 is unconnected to any portion of the contactplate I3. It will be understood that the number of contacts I4, I5, I6and their relative location, and the configuration of the contact plateI3, or plates if desired, may be of various numbers and forms, dependingon the number of circuits it is desired to control and the manner inwhich it is desired to control them.

Referring now more particularly to the unitary contact-terminal post I1shown in detail in Figures 2, 3, and 5. The contact-terminal post I1comprises a socket member 32 in which the contact I4 is reciprocablymounted. The socket member 32 is here shown as of generally squarecross-section, having opposite walls 33, 34 forming integral extensionsof the legs of a loop 35, the loop providing an aperture 36. The socketmember has opposite walls 31, 38, at right angles to the walls 33, 34,each wall 31, 38 being formed in halves 39, 40, the wall halves 39 beingintegral with the wall 33 and the wall halves 40 being integral with thewall 34. The wall halves 39, 40 are each provided at the bottom thereof(as viewed in Figure 5) with a lateral extension or foot 4|. The walls33, 34 are similarly each provided with a lateral extension or foot 42,these feet 42 being here shown as somewhat wider than the feet M on thewall halves 31, 38.

The opposite walls 33, 34 are provided with aligned apertures 43, 44,here shown as of square shape, in which apertures 43, 44 are slidablydisposed projections 45, 46, of rectangular crosssection, on a detentmeans 41. The detent means 41 is here shown as formed of sheet metal ofgenerally square dished form to fit slidably within the socket member32. The detent means 41 is here shown as provided with a hemisphericalprotuberance 48 pressed upwardly (as viewed 52 are generally rectangularin cross-section and have their upper margins, as viewed in Figure 5, inthe same plane as the upper margins of the apertures 43, 44. r Vapertures 52 are below the lower margins-of the smaller apertures 43,44.

The contact I4 is here shown as made of sheet metal and having a contactportion proper 53, with an outwardly curved surface, provided with twopairs of oppositely disposed legs54, 5-5 -and 56, 51 tapering towardtheir ends and extending at right angles to the contact portion proper53. The legs 54, 5'5, 56, 51 serve, among other things, to guide thecontact I4 for reciprocating movement in the socket member 32. The legs56, 51 are each provided with a laterally outwardly bent extension 58,of reduced width, .slidably disposed in the apertures 5I, '52. Disposedwithin the socket member 32, between the detent means 41 and the contactI4 is a helical spring '59, one end of which engages the inside of thedish shaped portion of the detent means 41 and the other end of whichengages the inside surface of the curved contact portion proper of thecon-' tact I4. The detent means 41 .is thus biased toward the right (asviewed in Figures 1, 2, and 3) toward the aperture 36 formed by the loop35; so that the'projections 45, 46, 49, 50 on'the detent means 41 engageand are stopped by the'right hand margins of the apertures 43,44, 5I,52in the walls 33, 34, 31, 38 of the socket member 32. In that position,the outside surface of the dished portion of the detent means 41 extendssomewhat beyond the right hand margins of the walls 31, 38, in theillustrated embodiment. At the same time, the spring 59 biases thecontact I4 in the opposite direction so that the lateralprojections 58engage and are stopped by the left hand margins of the apertures 5I, 52.

It will be evident from the hereinbef'ore described construction thatthe socket member 32, the loop 35, and the feet M, 42 may all be made ofa single piece of sheet metal. Before the loop 35 is fully bent totheform shown in the drawing, the detent means 41 is inserted within thewalls 33, 34, 31, 38 including also the spring 59 and the contact I4.The halves of the socket member 32 may then be moved toward each other,the detent 41, spring 59, and contact I4 having the positions shown inFigures 1, 2, and 3, when the free margins of the wall halves 39, 40 ofthe walls 31, 38 meet in lines or planes of contact 60. The assemblythen constitutes a self contained unitary contact-terminal post I1.

All that is necessary in order to mount the unitary contact-terminalpost H on theinsulating base 28 is to insert it through an aperture GIin the base, the aperture 61 being generally square in cross-section andf tting the exterior of the ,socket member 32. The aperture 6| may becountersunk by a generally cylindrical recess 62', so that the bottomsof the feet 4|, 42, will be flush with the front face of the insulatingbase 213. The tops of the feet 41., 42 bear against the The lowermargins of the I the outer faces of thewalls 31, 38.

The unitary contact-terminal posts I8, I9 are shown as identical withthe unitary contact-terminal post I1, and are insertable throughapertures in the base 20, identical with the apertures H for thecontact-terminal post I1, and require y no further description.

When the unitary contact-terminal posts I1,

1 I8, 49 havebeen assembled with the base 28, in

the manner already described in connection with the contact-terminalpost I1, the base 20 may then be assembled with and fastened to thecasing 2 I, and the springs 59 of the contact-terminal posts I1, I8 I9are thereby compressed to a predetermined extent by engagement of the.contacts I-4, I5, I 5 either with the contact plate 43 or with theinsulating disc I22. Thus the springs 53 serve to bias the respectivecontacts I4, :I5, I8 against the insulating disc I2 and the contactplate I3 and also serveto bias in the opposite direction the detentmeans 41 respectively asso ciated therewith.

Electrical connection may then be made to the contact-terminal posts I1,I8, I8 by inserting plug conductor terminals in the apertures formed bythe respective loops 35. One form of conductor terminal, 65, suitablefor use with the terminal receiving means is shown in Figure 3, thisconductor terminal 65 comprising a generally cylindrical portion 66having a frustro-conical 'end 61 and an annular furrow 68 in thecylindrical portion 86. The conductor terminal 65 may be fastened to aconductor 69 disposed therein, by swaging, as .indicated by swageindentations 18. When the conductor terminal 55 is inserted in theaperture 36, the frustro-conical portion '61 moves the detent means 41toward the left, as viewed in Figure 3, by cam action, against the biasof the spring 59, further inserting movement causing the hemisphericalportion 48 of the :detent means 41 to snap into the annularfurrow 68.Moreover, it will be evident that :each of the contact-terminal posts isassembled to the base 20 of insulating material in such a manner wherebythe socket or body portion 32 is held substantially in a fixed position,and this is very important for the reason that any accidental pull on aconductor wire secured to the socket will not disturb or otherwise breakthe electrical circuit between the. contact plate or bridge member I3and the contact associated with each socket. In other words, thecontacts carried by the socket members may laterally adjust themselvesor float with respect to the contact plate and the sockets. i i I I Itwill .be evident that the apertures 5|, of which there is one for eachunitary contactterminal post, I1,, I 8, I9 and-so on, being 0fnoncircular outline, conforming generally to the cross-sectional-outlineof the socket member 32, will prevent turning of the contact-terminalpost about their axes. 'A-lso, the apertures 6| have From the foregoingit will be apparent to those skilled in the art that the illustratedembodiment of my invention provides a new and improved electricalcontact and connection means, readily and conveniently constructed andassembled, and accordingly, accomplishes at least the principal objectof my invention. On the other hand, it also will be obvious to thoseskilled in the art that the illustrated embodiment of my invention maybe variously changed and modified, or features thereof, singly orcollectively, embodied in other combinations than those illustrated,without departing from the spirit of my invention, or sacrificing all ofthe advantages thereoit, and that accordingly, the disclosure herein isillustrative only, and my invention is not limited thereto.

What I claim and desire to secure by Letters Patent is:

1. Electrical connection means, comprising: a one piece tubular body,having a recess for receiving a conductor terminal, said body beingprovided with slot means in its side walls; a detent member reciprocablymounted in said body, and being constructed and arranged to cooperatewith said body recess and a conductor terminal disposed in said bodyrecess, said detent member having projection means projecting throughsaid side walls in said slot means for guidance; and a contact member,reciprocably mounted in said body, and having projection means alsoprojecting through said side walls in said slot means for guidance.

2. An electric switch including in combination, a casing, a switch backprovided with a seat including electrical connection means looselymounted in said seat, switching mechanism including a bridge membermovable within said casing for cooperation with said electricalconnection means, said electrical connection means comprising a bodyprojecting through said switch back and provided with a terminalreceiving aperture at its outer extremity, guideways provided in saidbody, detent means and a contact member carried by said body and havingmeans slidable in said guideways, and means for urging detent means andsaid contact member in opposite directions in a manner whereby saiddetent will retain a terminal pressed in said aperture, said contactmember will be directed to be engaged by said bridge member, and saidconnection means will be held in said seat.

3. An electrical apparatus including in combination, a bridge member, aninsulator provided with a seat including electrical connection meansloosely mounted in said seat, said electrical connection meanscomprising a body member projected through said insulator and providedwith a terminal receiving aperture at its outer extremity, guidewaysprovided in said body, detent means and a contact member carried by saidbody and having means slidable in said guideways, and means for urgingsaid detent means and said contact member in opposite directions wherebysaid detent will retain a terminal pressed in said aperture, saidcontact member will be directed to be engaged by said bridge member, andsaid connection means will be held in said seat.

HARRY A. DOUGLAS.

